//
// Created by Kirill Zhukov on 20.04.2025.
//

#ifndef SHAREDCOMMANDQUEUE_H
#define SHAREDCOMMANDQUEUE_H

#include "Command.h"
#include "utils/datastructures/LFCircullarBuffer.h"
#include <atomic>
#include <cstdint>

namespace usub::core {
    constexpr size_t SHM_ALIGNMENT = 64;

    class alignas(SHM_ALIGNMENT) SharedCommandQueue {
    public:
        explicit SharedCommandQueue(size_t capacity);

        ~SharedCommandQueue();

        bool try_push(const Command &cmd);

        bool try_push_batch(const Command *cmds, size_t count);

        void finalize(Command *cmd);

        std::optional<Command> try_pop();

        size_t try_pop_batch(Command *out, size_t max_count);

        Command *peek(size_t index);

        void pop();

        size_t pending_count() const;

        Command *raw_buffer() noexcept;

        size_t capacity() const noexcept;

        std::atomic<size_t> &head() noexcept;

        std::atomic<size_t> &tail() noexcept;

        bool enqueue_put(const usub::utils::Hash128 &key, const std::string &value);

        bool enqueue_find(const usub::utils::Hash128 &key);

        static bool await_response(Command &cmd);

        void reset();

        static size_t calculate_shm_size(size_t capacity);

    private:
        size_t capacity_;
        alignas(SHM_ALIGNMENT) std::atomic<size_t> head_;
        alignas(SHM_ALIGNMENT) std::atomic<size_t> tail_;
        alignas(SHM_ALIGNMENT) Command buffer_[];
    };
}


#endif //SHAREDCOMMANDQUEUE_H